Zebrafish have become one of the most important research species in biomedical science, but welfare standards for this species have lagged behind those for rodents. Improving zebrafish welfare is increasingly recognized as essential.
Zebrafish welfare represents an area where rapid expansion of use has outpaced welfare science and regulatory attention. The species' transparency and genetic tractability make it invaluable for biomedical research, but these scientific advantages should not translate into welfare indifference. Zebrafish experience pain, stress, and behavioral disruption from environmental inadequacy and experimental procedures. The evidence base for zebrafish sentience and welfare responses has grown substantially in the past decade, making the current gap between zebrafish and rodent welfare standards increasingly unjustifiable. The key improvements needed are: better water quality monitoring, group housing with enrichment as standard, analgesia protocols for painful procedures, and behavioral welfare assessment as part of study design.